A UN special investigator is urging the world body to open an enquiry into North Korea for possible crimes against humanity.

UN special rapporteur Marzuki Darusman is recommending that the Geneva-based Human Rights Council investigate North Korea's "grave, widespread and systematic violations of human rights."

Darusman's report on Tuesday says a review of the isolated country's record since 2004 shows the need for a probe to fully document the responsibility of government and individuals for alleged abuses "in particular where they amount to crimes against humanity."

The report cites nine patterns of violations such as prison camps and using food to control people.

In a lengthy response, North Korea's UN mission in Geneva calls the new UN report "politically motivated."